International Patent Publication No. WO 2010/025824 A2 describes apparatuses by means of which dialysis liquid is heated by means of a heating bag during a dialysis treatment. Heating takes place while the dialysis liquid flows through the heating bag, before the dialysis liquid is introduced into the dialyzer or blood treatment filter, in which substances are exchanged between blood and dialysis liquid via a—usually semipermeable—membrane.
Under certain operating conditions, it can however not be excluded, without having taken countermeasures, that the heating bag bursts due to the pressure built up by the pump which conveys the dialysis liquid through the heating bag. Bursting could take place especially in arrangements in which the heating bag is arranged on the pressure side of the pump—for example to avoid precipitations in the tube system. Bursting of the heating bag may pose a danger to the patient, at least if it is not noticed in time.